The present invention relates to an automated system for structurally joining at least two main portions making up the chassis of a vehicle or the fuselage of an aircraft or the hull of a boat. Said system can automatically and continuously handle all the steps of the associated method for joining the portions. Said system can handle the entire kinematic/mechanic chain for manufacturing said vehicle or aircraft or boat.
The associated method of assembly concerns the steps carried out by the system for assembling chassis or fuselage or hull portions, which steps are carried out automatically and are highly reproducible.
Preferably, said system and the associated method are applicable for manufacturing aircraft fuselages by joining at least two fuselage sections.
It is known that assembling the sections of an aircraft fuselage is a very complex task that requires much control in order to create an aircraft capable of passing the flight resistance tests. In fact, if such sections are not properly assembled, the resulting aircraft will suffer stability and aerodynamics problems, which may endanger the utilization of the aircraft thus assembled.
Systems for joining at least two fuselage sections are known which comprise a plurality of sensors adapted to facilitate the steps of positioning, moving and joining said sections, which are carried out by assembly personnel. In fact, most of the steps of the methods for manufacturing an aircraft described in the prior art are carried out by human personnel with the help of electromechanical devices and sensors of various nature.
For this reason, when manufacturing an aircraft, errors may be made due to the human component while executing one or more steps of the method for assembling and joining the aircraft sections.
Automatic devices are known which are adapted to carry out one or more steps of the method for manufacturing an aircraft; said devices are supervised by an assembly operator. Therefore, in order to join sections of an aircraft, the operator will have to supervise a plurality of automatic devices. Manufacturing an aircraft in compliance with assembly standards strongly depends on the skills of the assembly operator, who is in charge of coordinating the various devices and possibly also supervising any manually executed operations.
A method of this type turns out to be very costly, because it requires the use of many electromechanical devices that must be made to interact with one another, and also because of the large number of manual operations involved. In addition, such a method is also costly in terms of production time per aircraft, because the various steps must be supervised by the person in charge, although with the help of sensors of various kinds, who must supervise every critical aspect of the aircraft production process.
Finally, this type of method, the implementation of which requires a human component, introduces an uncertain variable which makes the method hardly reproducible and which, in probabilistic terms, causes high uncertainty as to the result thereof. Such uncertainty implies increased average aircraft production costs.
It should also be underlined that each electromechanical device used for implementing the method introduces intrinsic uncertainty in the operations it is adapted to perform; such uncertainty adds up to the uncertainties of the other electromechanical devices, because the systems known in the art do not include a central control system capable of coordinating such electromechanical devices to eliminate any errors so as to reduce the uncertainty of the entire system and, as a consequence, of the manufacturing method.
Junction errors are also due to intrinsic physical factors, such as thermal or mechanical expansion of metal parts, depending on the temperature and humidity present in the place where the assembly process is being carried out.
Checks are also known to be made on the junction by means of laser measurements taken at discrete instants while executing the joining method.
However, such checks do not ensure junction repeatability and correct alignment of all of the key points required for properly joining the parts.